Ok so i have a iphone 4 8gb on 5.1.1 with t-mobile unlocked legit with baseband 4.12.01

At the min when i respring and reboot i get around 370MB free of ram .......is this good or can i improve the ram space .....i have had it up too around 404mb a few months ago and can't seem to get back there. Even if i delete a few things.
Is there anythink i can download to free some space up .....i do use icleaner but i get less space when used lmao.

Also i lose around 100mb just unlocking the screen ?

Any info on any tips to free ram or cydia downloads would be cool thanks also is 370mb good that i have at the min.

Edit: just did a reboot and unlocked then opened music and ram has gone down to 132mb ?